Walter Su created HDFS-8461:
-------------------------------
Summary: Erasure coding: fix priority level of
UnderReplicatedBlocks for striped block
Key: HDFS-8461
URL: https://issues.apache.org/jira/browse/HDFS-8461
Project: Hadoop HDFS
Issue Type: Sub-task
Reporter: Walter Su
Assignee: Walter Su
{code:title=UnderReplicatedBlocks.java}
private int getPriority(int curReplicas,
...
} else if (curReplicas == 1) {
//only on replica -risk of loss
// highest priority
return QUEUE_HIGHEST_PRIORITY;
...
{code}
For stripe blocks, we should return QUEUE_HIGHEST_PRIORITY when curReplicas ==
6( Suppose 6+3 schema).
That's important. Because
{code:title=BlockManager.java}
DatanodeDescriptor[] chooseSourceDatanodes(BlockInfo block,
...
if(priority != UnderReplicatedBlocks.QUEUE_HIGHEST_PRIORITY
&& !node.isDecommissionInProgress()
&& node.getNumberOfBlocksToBeReplicated() >= maxReplicationStreams)
{
continue; // already reached replication limit
}
...
{code}
It may return not enough source DNs ( maybe 5), and failed to recover.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
